The Effect of Spool Displacement Control to the Flow Rate in the Piezoelectric Stack-Based Valve System Subjected to High Operating Temperature

Abstract

This work investigates the effect of spool displacement control of the piezoelectric stack actuator (PSA) based valve system on the flow motion of the pressure drop and flow rate. As a first step, the governing equations of the structural parts of the displacement amplifier and spool are derived, followed by the governing equation of the fluid part considering control volume and steady flow force. Then, an appropriate size of the valve is designed and manufactured. An experimental apparatus to control the spool displacement is set up in the heat chamber and tracking control for the spool displacement is evaluated at 20 °C and 100 °C by implementing a proportional-integral-derivative (PID) feedback controller. The tracking controls of the spool displacement associated with the sinusoidal and triangular trajectories are realized at 20 °C and 100 °C. It is demonstrated that the tracking controls for the sinusoidal and triangular trajectories have been well carried out showing the tracking error less than 3 μm at both temperatures. In addition, the flow motions for the pressure drop and the flow rate of the proposed valve system are experimentally investigated. It is identified from this investigation that both pressure drop and flow rate evaluated 20 °C have been decreased up to 18% at 100 °C. This result directly indicates that the temperature effect to control performance of the structural part and fluid part in the proposed PSA based valve system is different and hence careful attention is required to achieve the successful development of advanced valve systems subjected to a wide range of the operating temperature.

Mass flow rate control of solenoid-based injectors

“…The error rate of the mass flow rate control was less than 1.06% for low amplitudes and frequencies which verified the effectiveness of the algorithm used. This is similar to the error rate reported for piezoelectric actuated injectors, for example, by Park et al 33…”

Review of Recent Advances in the Drive Method of Hydraulic Control Valve

“…Han C et al [6,11] also proposed a similar actuation scheme. Yu-Park YJ et al [79] proposed a piezoelectric stack actuator based on a valve system, which works on the same principle as a B-type proportional valve, but there are differences in the drive method. In the B-type proportional valve, the output shaft of the piezoelectric stack actuator pulls the spool movement through a lever; in the valve-system-based piezoelectric stack actuator, the piezoelectric stack actuator pushes the spool movement through a lever.…”